线路型避雷器的应用

输电线路跳闸原因约有60％是因为雷击输电线路引起的,所以,采用线路型避雷器降低线路的雷击跳闸率是很有必要的。为此,对线路型避雷器分类作了介绍,并对各类线路型避雷器原理及应用作了详尽的介绍分析。从已安装了线路型避雷器的输电线路运行情况来看,线路型避雷器在输电线路防雷及变电站防止雷电侵入波方面发挥了重要的作用。     

750 kV输变电示范工程单相人工接地故障试验现场实测和计算分析

应用电磁暂态计算程序(electromagnetictransientprogram,EMTP)对安装金属氧化物避雷器的35kV配电线路的耐雷水平进行了分析计算。具体比较了雷击有、无避雷线的线路,采取不同避雷器安装方案时的耐雷水平;分析了杆塔冲击接地电阻、绕击导线位置对耐雷水平的影响。仿真计算结果表明,安装线路避雷器﹑减小杆塔的接地电阻可有效提高35kV配电线路的耐雷水平。对于35kV有避雷线配电线路,加装线路避雷器后可显著降低其发生绕击闪络的概率。     

35kV输电线路避雷器的雷电放电电流和吸收能量

在建立输电线路防雷计算模型的基础上,用电磁暂态计算程序对有、无避雷线的35 kV输电线路避雷器的雷电放电电流和吸收的雷电放电能量进行了计算。具体计算了不同幅值的雷电流作用下,不同冲击接地电阻时,线路上避雷器的放电电流和吸收的比能量,讨论了雷电流、接地电阻对放电电流和比能量的影响,并对分别装在有、无避雷线的输电线路上的避雷器的放电电流和比能量进行了纵向比较分析。     

高压输电线路防雷保护的若干问题

概述了线路雷电性能计算用参数和方法。讨论了各种改善线路雷电性能的措施。指出线路金属氧化物避雷器(MOA)在实践中的良好效果并对其应用提出了建议。     

Development and applications of lightning arresters fortransmission lines

A lightning arrester with a series gap for transmission lines has been developed to prevent faults due to lightning. It has shown excellent performance since 1986 on 77 kV service lines in heavy lightning regions. A 275 kV lightning arrester has also been developed, and a field test was started on a service line in 1988. The authors describe the requirements for lightning arresters for transmission lines, design concepts, specifications, and operational records on the 77 kV lines for three years. The gapped-type lightning arrester is considered the most practical given the existing technology. To obtain light and small lightning arresters, an ethylene-propylene rubber shed was adopted for external insulation and a special pressure relief mechanism was introduced in place of the pressure relief guide of the station arresters. The follow current can be cut off within a period of 0.25 to 0.5 cycles even under contaminated and wet conditions     

采用避雷器防止10kV架空绝缘导线雷击断线

在绝缘导线应用于配电线路的建设中,10 kV架空线路雷击断线事故是影响安全供电的大问题.通过分析架空绝缘导线雷击断线的机理,介绍安装线路型金属氧化物避雷器可有效限制雷电过电压对配电线路的危害,减少绝缘导线配电线路的雷击断线事故,保证配电线路的安全运行,指出安装线路型避雷器这一防雷技术存在的问题,并分析了线路型避雷器的安装密度和保护效果.     

采用MOA的输电线路雷电响应分析模型

用ATP仿真研究了 110kV线路雷击响应的一些杆塔和线路模型 ,指出分段传输线模型是较合理的杆塔模型。仿真结果有助于制定用带串联间隙线路避雷器来降低线路雷击事故的相应措施。     

Transmission line arrester energy, cost, and risk of failureanalysis for partially shielded transmission lines

Application of metal oxide surge arresters in power systems has been traditionally linked to electrical equipment protection. The industry has noted a very significant increase in the application of metal oxide arresters on transmission lines in an effort to reduce lightning initiated flashovers. This paper describes a cost-effective installation of surge arresters on a partially shielded transmission line. It compares several options with respect to cost and gains in terms of lightning performance improvement. This paper also presents a new approach to calculate risk of failure of transmission line surge arresters (TLSAs) due to lightning strokes to towers, shield/phase conductors, and illustrates the method with an example for a partially shielded line. Results show that the risk of failure is very small. The installation of TLSAs completed in 1997 demonstrated that it is possible to afford adequate lightning protection levels by selectively applying surge arresters only to the towers most sensitive to backflashover and shielding failures     

外串间隙线路型避雷器在架空输电线路中的防雷作用

针对阳江地区输电线路存在遭受严重雷击跳闸的问题,分析了各种雷击过电压引起的线路闪络跳闸,介绍了外串间隙线路型避雷器在输电线路中间防雷的机理,指出在阳江电网中应用外串间隙线路型避雷器解决架空输电线路中间防雷的必要性及避雷器的安装选点原则,可供同行参考。     

Investigation of effect of transmission line arresters verified by lightning surges at substations

In recent years, transmission line arresters have been installed to protect overhead power transmission lines from backflashovers caused by lightning. In addition, it has been expected that substation lightning surges incoming via transmission lines can be suppressed by them. However, the suppression effect by those with series gaps has not been investigated sufficiently. The author has measured lightning surges at two 77‐kV substations from 1990 to 1993. As the transmission line arresters have been mounted on the towers since 1992, the lightning surges due to the sparkover of the series gap of the transmission line arresters can be observed at the substations. In this paper, the lightning surge waveforms due to such sparkover have been analyzed in detail. Next, an accurate EMTP simulation method considering the induced lightning surge voltages has been proposed. Finally, their suppression effect has been investigated by simulation corresponding to each mounting method. © 1999 Scripta Technica, Electr Eng Jpn, 126(4): 30–39, 1999     

Assessment of surge arrester failure rate and application studies in Hellenic high voltage transmission lines

The use of transmission line surge arresters to improve the lightning performance of transmission lines is becoming more common. Especially in areas with high soil resistivity and ground flash density, surge arresters constitute the most effective protection mean. In this paper a methodology for assessing the surge arrester failure rate based on the electrogeometrical model is presented. Critical currents that exceed arresters rated energy stress were estimated by the use of a simulation tool. The methodology is applied on operating Hellenic transmission lines of 150 kV. Several case studies are analyzed by installing surge arresters on different intervals, in relation to the region's tower footing resistance and the ground flash density. The obtained results are compared with real records of outage rate showing the effectiveness of the surge arresters in the reduction of the recorded failure rate. The presented methodology can be proved valuable to the studies of electric power systems designers intending in a more effective lightning protection, reducing the operational costs and providing continuity of service.     

Distribution arrester outages caused by lightning backflow current flowing from customer's facility into power distribution lines

Direct lightning strokes are considered to be a main cause of damage to surge arresters on power distribution lines. Recently, lightning performance of distribution lines has been observed using still cameras, and lightning‐caused distribution outages on hilltop areas on the coast of the Sea of Japan have been investigated. This research has shown a possibility that lightning backflow current flowing from customer facilities into distribution lines causes damage to surge arresters on the distribution lines. We have investigated the lightning backflow current flowing from customer facilities into distribution lines as a cause of damage to surge arresters. The main results are as follows: (1) The electric charge of the backflow current flowing into distribution lines is more than 60% of that of the lightning stroke current. (2) If the grounding resistance of the customer's facility is not low, the failure rates of a surge arrester caused by backflow current due to winter lightning is more than 90% of that caused by direct lightning strokes. © 1999 Scripta Technica, Electr Eng Jpn, 126(3): 9–20, 1999     

Use of line surge arresters for the improvement of the lightningperformance of 63 kV and 90 kV shielded and unshielded transmissionlines

The lightning performance of 63 kV and 90 kV shielded and unshielded power transmission lines, protected by surge arresters are considered. A specialized software package is used for the computation of the line's fast front transients. A Monte Carlo statistical method, together with a three-dimensional electrogeometric model is used to determine the lightning stroke locations. Different arrester installation configurations are analyzed and compared. The energy duties of the transmission line surge arresters are computed statistically     

多重雷击引起220kV断路器损坏的事故分析

针对220 kV线路雷击故障时雷电波侵入220 kV变电站内,引起220 kV断路器断口绝缘击穿,导致断路器内部损坏,建议开展110、220 kV SF_6断路器雷电冲击、反极性工频联合电压试验,并在强雷地区变电站110、220 kV架空出线侧加装避雷器保护。这些线路避雷器除了能防止断口内外闪络,也可以保护母线上的其他电气设备,显著地减少雷击的危害。     

应用线路避雷器提高交流输电线路耐雷水平

线路避雷器在雷电活动强烈、降低杆塔接地电阻困难的特殊线段上使用 ,可有效提高输电线路的耐雷水平。耐雷水平的提高与线路避雷器的安装方式和安装组数有关 ,且应尽量降低杆塔的冲击接地电阻。线路避雷器仅能保护安装了线路避雷器的杆塔自身的线路绝缘子 (串 )不发生雷击闪络 ,无外延的雷击保护范围。     

山区架空输电线路防雷技术研究

为了解决广西电网山区高杆塔输电线路雷击跳闸率高的问题,利用ATPDraw仿真软件研究分析在输电线路高杆塔上架设避雷器和用滚球法原理安装避雷侧针的理论防雷效果,并对广西电网雷击跳闸率较高的输电线路进行防雷措施试点改造,对雷电易击段有选择性地采取装设线路避雷器、加强线路绝缘和装设防绕击避雷针等综合防雷技术措施,改造后的输电线路雷击跳闸率逐年下降。     

一起雷电引发220kV断路器爆炸事故的分析

阐述了一起雷电引发220kV SR断路器爆炸事故的情况,结合事故的遥视系统监控录像、故障录波图、保护动作、现场检查情况以及事故线路附近雷电定位数据,分析了雷击形式和断路器爆炸的原因及影响因素,并对照分析了站内加装出线避雷器和装设线路避雷器这两种防范措施,讨论了运行和反事故措施的一些注意事项。     

层次分析法在输电线路综合防雷措施评估中的应用

基于层次分析法(Analytic Hierarchy Process,AHP)的基本原理,建立了一个用于评估输电线路防雷措施的层次分析结构模型,以某220kv实际线路为例对各种措施进行综合评估和计算,得到了该线路防雷改造方案的优先次序:降低接地电阻、架设耦合地线、增加避雷线根数、安装线路型避雷器、增加两片绝缘子.     

输电线路避雷器断串分析与防范

目前采用的线路型避雷器多为绝缘子间隙避雷器。运行单位在安装线路避雷器时主要考虑的是避雷器的电气性能,很少对避雷器的安装形式和运行状态下的受力情况进行分析,以至运行中出现掉串现象。例举了一起线路型避雷器断串缺陷,通过计算分析得出断串的原因,并提出了避雷器安装的防范措施。     

220kV引两双回雷击跳闸原因分析

减少避雷线的保护角或采用负保护角,在架空线路下架设耦合地线,在杆塔或避雷线上安装方绕击侧向针,在同塔双回线路雷击易击段的杆塔上均安装线路避雷器,可以采用差绝缘配置方案,其中一回线路采用并联间隙或线路避雷器进行防雷保护,另一回线路的绝缘水平适当加强或保持不变。